coagulum

Coagulum is a coagulated mass formed when a liquid containing suspended particles or colloids undergoes coagulation. It is a semisolid lump that results from the aggregation of dispersed molecules, usually proteins, as the liquid phase becomes destabilized. The term is used in biology, medicine, and food science, and is sometimes treated as synonymous with clot, though coagulum more often refers to a non-blood coagulation product or a general lump.

Formation and factors: Coagulation is driven by physical or chemical changes that cause proteins to unfold and link into a network that traps water. Temperature, pH, enzymatic action, and the presence of coagulants such as acids, rennet, or certain salts influence the strength and texture of the coagulum. In dairy, milk coagulates into curd when acid or rennet cleaves casein proteins, forming cheese curds; heating with acid can also form a coagulum.

Applications and examples: In food production, coagula form the basis of cheese and many dairy products, or can indicate curdled milk. In medicine, blood coagulation produces a clot (or thrombus) that helps stop bleeding; the resulting mass is sometimes described as a coagulum in older texts, though modern terminology typically distinguishes clot from other coagulated masses.

Etymology: From Latin coagulum, meaning a lump formed by coagulation, from coagulare, to coagulate.